Transfer presses are generally used in metal-stamping operations and in particular for deep-drawn metal forming operations. Such a press typically includes numerous sequentially-arranged stations each of which receives and transfers a metal blank as it is being successively formed into its desired shape along numerous die (that is to say, working) stations.
Typically, the transfer press includes one or more idle stations situated between the successive punch-and-die stations as a way to provide locating and positioning functions for the workpiece being formed. Because the workpiece may be of different sizes or shapes, it is beneficial to provide the idle stations with the ability to accurately and adaptively support, position and locate such pieces, regardless of their size or shape. One conventional way to achieve this is to have the workpiece-holding portion of the idle station be of divided construction so that they can be split laterally (i.e., sideways) relative to the direction of travel of the workpiece as it traverses the transfer press. During such splitting, an operator unhooks a hinged, spring loaded handle from a retainer and pulls one half of the part-holding portion of the idle station toward him or her, while the other half moves in an opposing direction via cable or related linkage. Idle stations configured to have such divided construction are known as split idle stations.
In conventional design, various locking schemes are used to keep split idle station components temporarily in place. In one known form as shown in FIG. 2, such locking is used to keep a workpiece-holding bracket in place during idle station use. Conventionally, when a pin or related protruding mounting part of the bracket is inserted into a complementary-sized and shaped hollow shaft or channel 45 within a holder 40 that includes a handle 41, biasing spring 42 and lever 43 movable about a pivot point 44, the biased construction allows an interference fit to be formed with a circumferentially notched portion that is formed around the periphery of the pin that is inserted along its axial (that is to say, longitudinal) dimension beyond the position within the channel 45 where the lever 43 is located. Details of these various components used in holder 40 are shown by removing cover 46 and fasteners 47. While generally useful for their intended purpose, such a locking configuration requires a two-hand operation to release the bracket. For example, an operator of the idle station must use one hand with which to pull on the handle 41 to overcome the spring bias as a way to temporarily unseat the lever 43 from the notch, while the other hand is used to lift the bracket out of engagement with the holder 40. The author of the present disclosure has determined that such two-handed operation is cumbersome, and that a simplified approach to connecting and disconnecting a workpiece-holding bracket is warranted.